I pulled out the solder iron & bypassed the passive crossovers in my AL-IIIs today; it took about 2 hours all told to get the Ashley crossover installed (what a snakes nest behind the unit now with 5.1 setup!!) and unsolder the x-over and solder the speakers back inline with the fuses*.

*Should I be using a lower rated fuse now without the crossovers installed??

About 15 seconds after I finished & was connecting the last speaker to the amp, a major storm blew through and knocked out our power for about 2 hours!!

The power came back on about the time & had decided to just go to bed, so I ran upstairs & got everything prepped, turned it on, adjusted the crossover and discovered....

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I HATED the sound coming out of the ribbons (nasal-ish sounding), and the bass was weak!

SO, I did some playing around with the levels, gave a little bit of treble boost via the TG-IV, and it's now sounding MUCH better, although I realize I'm not going to be happy until I get the Rane parametric equalizers in place (20 minutes left on the auction as I type this!) & shape the sound a little. First impression is the upper midrange is boosted a LOT with this direct connection, but I can also tell a lot of power has been freed up from the amp. The AL-III x-overs are real power hogs~

FYI: Right now-just based on what I hear, I've got the woofers bumped up about +2.5 (not sure if that's dB or what, but that's on the Ashley's scale) and the ribbons -1.0 for level, then the crossover is set to 200 Hz with a 6 dB/octave slope (Linkwitz-Riley filter).

Last edited by TNRabbit on Wed Jun 23, 2010 6:40 am, edited 1 time in total.

TNRabbit wrote:Interesting, they just sound "faster" and tighter than before...like they've been released from some sort of sonic molasses....??

Not sure what I mean by "faster", but that's the only term I can come up with to describe it~

I think I've found out why it sounds tighter/faster:

"with an active crossover, the power amplifiers are directly connected to the speaker drivers, thereby maximizing amplifier damping control of the speaker voice coil, reducing consequences of dynamic changes in driver electrical characteristics, all of which are likely to improve the transient response of the system"

Active Bi-Amping FAQ for anyone wondering what the hell it is I'm doing:

“What is Active Bi-Amping?”

Active bi-amping uses one amplifier for low frequencies and another for mid/high frequencies—per audio channel. This is done via the use of an active crossover unit which is inserted between the preamplifier and power amplifiers.

“What are the advantages of active bi-amping?”

1) It provides much greater driver control than a passive crossover/full-range-loaded amplifier configurations.

2) It provides a better load for your amplifiers to drive, and an effective gain in each amplifier’s effective output. It will provide lower amplifier-originated intermodulation distortion (IMD).

3) It provides much greater protection of your tweeter/midrange drivers under clipping/overload conditions.

4) It provides the ability to use less expensive amplifier designs for each driver.

5) It provides for time alignment of drivers within a single speaker (a “must have” capability)

6) It provides for better crossover performance in both amplitude AND phase in the crossover region for smoother crossover performance, including more stable soundstage imaging vs. frequency.

2) It provides higher-quality equalization (“EQ”) capability for each channel.

3) Digital crossovers typically provide for delay to allow for time alignment of the drivers within a single speaker. (This is a similar function to an AV Processer that time aligns speaker-to-speaker in a 5.1/7.1 array.)

Yes. At least the woofer (or low frequency driver) must be disconnected from the passive crossover to permit bi-amping. If your speakers are 3-way (i.e., woofer, midrange, tweeter in each cabinet), then you may retain the passive crossover between the midrange and the tweeter if using bi-amping (…but for tri-amping, all drivers must be disconnected from the passive crossover networks)

Can I use ‘passive bi-amping’?”

Passive bi-amping does not bring the benefits of active bi-amping, only the disadvantages of extra cables and connectors. Generally, it may not worth the expense of the extra amplifier, depending on your speaker power requirements. In particular, passive bi-amping does not provide for delay adjustment or filter/EQ parameter flexibility.

Have I seen active crossovers used in configurations other than a active crossover box?

Probably--the "powered subwoofer" channel found on most AV Receivers/Processors is a limited example of a for-purpose active crossover channel (i.e., mono bass channel). Usual features include gain control (at the integrated subwoofer/power amplifer unit), user selectable crossover frequencies, and sometimes Geometric GEQ/PEQ (graphical and parametric equalizer) filters built into the AVR/AVP.

Delay adjustment for each speaker channel is usually included in the AVR processor functionality to correct for speaker distance room placement variances. Additionally, an "Audyssey"-like feature on some AVRs/AVPs features a built-in real-time analyzer (RTA) to help the user set up their speakers in a room environment.

Now that you've got that crossover out, can you diagram it for us. I count the three pots, six inductors, three film caps (yellow), two electrolytics (black and blue) and four power resistors (white and one of them really big). No one has a diagram, and we AL-III owners could really use one. There might be something hidden I can't see (especially under that film cap on the top pot).